BIOL 530
We will use the latitudinal increase in diversity towards the equator as a launching point to explore how diversity forms, is maintained, and disappears, and why we find such dramatic variation in diversity around the world.
Course discussions will focus on both evolutionary and ecological perspectives of diversity, and we will review various hypotheses to explain latitudinal diversity gradients.
Class schedule
Mondays 08:30 - 10:00am & Thursdays 10:00 - 11:30am
Week 1 Thursday, Sept 4, 2025 Introduction & complex questions in science
Week 2 Monday, Sept 8, 2025 Strong inference
Thursday, Sept 11, 2025 Multiple working hypotheses
Week 3 Monday, Sept 15, 2025 Biological patterns across latitude
Thursday, Sept 18, 2025 A framework for studying diversity gradients
Week 4 Monday, Sept 22, 2025 The latitudinal gradient through deep time
Thursday, Sept 25, 2025 Latitudinal Variation in Cladogenesis
**Student presentations begin**
Week 5 Monday, Sept 29, 2025 Latitudinal Variation in Extinction - Teddy (presenter), Gabby (co-presenter)
Thursday, Oct 1, 2025 Janzen's Hypothesis - Harani (presenter), Brooke (co-presenter)
Week 6 Monday, Oct 6, 2025 Asynchrony of Seasons Hypothesis - Taylor (presenter), Ausha (co-presenter)
Thursday, Oct 9, 2025 Shifting Ranges Hypothesis - Serena (presenter), Kira (co-presenter)
Week 7 Reading week (October 13-17)
Week 8 Monday, Oct 20, 2025 Species Energy - Rates of Evolution Hypothesis - Trinity, (presenter), Mya (co-presenter)
Thursday, Oct 23, 2025 Biotic vs Abiotic Selection Hypothesis - Romta (presenter), Teddy (co-presenter)
Week 9 Monday, Oct 27, 2025 Geographic Area Hypothesis - Brooke (presenter), Taylor (co-presenter)
Thursday, Oct 30, 2025 Species Energy - Number of Individuals Hypothesis - Eva (presenter), Amelie (co-presenter)
Week 10 Monday, Nov 3, 2025 Glacial Extinctions Hypothesis - Nicole (presenter), Romta (co-presenter)
Thursday, Nov 6, 2025 Tropical Niche Conservatism Hypothesis - Mya (presenter), Serena (co-presenter)
Week 11 Monday, Nov 10, 2025 Density-dependent Mortality Hypothesis - Ausha (presenter), Eva (co-presenter)
Thursday, Nov 13, 2025 Climate Stability - Population Size Hypothesis - Kira (presenter), Harani (co-presenter)
Week 12 Monday, Nov 17, 2025 Biotic Interactions - Ecological Breadth Hypothesis - Amelie (presenter), Nicole (co-presenter)
Thursday, Nov 20, 2025 Evolutionary Time Hypothesis - Gabby (presenter), Trinity (co-presenter)
Week 13 Monday, Nov 24, 2025 Environmental Harshness Hypothesis - Vennila (presenter), Zainab (co-presenter)
Thursday, Nov 27, 2025 Geometric Constraints Hypothesis - Zainab (presenter), Vennila (co-presenter)
Week 14 Monday, Dec 1, 2025 Wrap-up discussion
Grade breakdown
Presentation of hypothesis & predictions 30% instructions & rubric
Co-presentation of critical assessment 15% instructions & rubric
Major written paper 35% instructions & rubric
In-class participation 20% instructions & rubric
There are no formal exams in this class.
Class readings (I will send out readings each week by email)
Week 1 Thursday, Sept 4, 2025 no readings
Week 2 Monday, Sept 8, 2025 Platt 1964 Science 146:347-353
Thursday, Sept 11, 2025 Chamberlin 1965 Science 148:754-759
Week 3 Monday, Sept 15, 2025 Hillebrand 2004 American Naturalist 163: 192-211
Thursday, Sept 18, 2025 Jablonski et al. 2006 Science 314: 102-106
Week 4 Monday, Sept 22, 2025 Mannion et al. 2014. TREE 29: 42-50
Thursday, Sept 25, 2025 Weir & Schluter 2007 Science 315: 1574-1576
**Student presentations begin**
Week 5 Monday, Sept 29, 2025 Martin et al. 2007 J. Evol. Biol. 20: 930-93
Thursday, Oct 1, 2025 Ghalambor et al. 2006 Integr. & Comp. Biol. 46: 5-17
Week 6 Monday, Oct 6, 2025 Martin et al. 2009 Ideas Ecol. Evol. 2: 9-17
Thursday, Oct 9, 2025 Dynesius & Jansson 2000 PNAS 97: 9115-9120
Week 7 Reading week (October 13-17)
Week 8 Monday, Oct 20, 2025 Allen et al. 2006 PNAS 103: 9130-9135
Thursday, Oct 23, 2025 Schemske 2009 book chapter
Week 9 Monday, Oct 27, 2025 Rosenzweig 1992 J. Mammalogy 73: 715-730
Thursday, Oct 30, 2025 Wright 1983 Oikos 41: 496-506 &
Currie & Paquin 1987 Nature 329: 326-327
Week 10 Monday, Nov 3, 2025 Adams & Woodward 1989 Nature 339: 699–701 &
McGlone 1996 Global Ecol. Biogeogr. Letters 5: 309-314
Thursday, Nov 6, 2025 Wiens & Donaghue 2004 TREE 19: 639-644
Week 11 Monday, Nov 10, 2025 Hille Ris Lambers et al. 2002 Nature 417: 732-735
Thursday, Nov 13, 2025 Connell & Orias 1964 Am. Naturalist 98: 399-414
Week 12 Monday, Nov 17, 2025 Dyer et al. 2007 Nature 448: 696-699
Thursday, Nov 20, 2025 Fischer 1960 Evolution 14: 64-81 (excerpt only)
Week 13 Monday, Nov 24, 2025 Brown & Gibson 1983 (excerpt from book) &
Thiery 1982 Biological Reviews 57: 671-710 (excerpt)
Thursday, Nov 27, 2025 Colwell & Lees 2000 Trends in Ecology & Evolution 15:70-76
Week 14 Monday, Dec 1, 2025 Jetz & Fine 2012 PLoS Biology 10: e1001292
